Cal. 2120 finely pierced and engraved gilt-finished lever movement 36 jewels the pierced and engraved rotor depicting the letters AP and with 21K gold rim the skeletonized dial with five minute divisions on outer white chapter ring four subsidiary dials indicating month day date and phases of the moon combined with lunar calendar the water-resistant-type case with octagonal bezel secured by eight white gold screws screw down crown the glazed display back secured by eight screws stainless steel Audemars Piguet link bracelet and deployant clasp case dial and movement signed